Humidifier



FIG. 1 is a front perspective view of a humidifier showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevation view thereof, on a reduced scale;

FIG. 4 is a left side elevation view thereof, on a reduced scale;

FIG. 5 is a right side elevation view thereof, on a reduced scale; and,

FIG. 6 is a rear elevation view thereof, on a reduced scale.

The bottom view (not shown) forms no part of the claimed design. The subject matter shown in broken lines forms no part of the claimed design. 

The ornamental design for a humidifier, as shown and described. 